Brucella ovis excretion in semen of seronegative, clinically normal breeding rams.
A commercial flock of Suffolk and Suffolk-cross breeding rams was monitored for 5 years in an effort to control epididymitis caused by Brucella ovis. Scrotal palpation, semen evaluations, and vaccination against B ovis were used the first 3 years. Serologic evaluation (complement fixation and ELISA) was added the fourth year, and bacteriologic culturing was added to the program the fifth year. Semen culturing in the fifth year revealed 9 (37.5%) of 24 rams were actively excreting B ovis; 6 of those 9 rams were seronegative. Neither semen quality nor the presence of WBC in the semen were dependable criteria to detect these seronegative carriers. In spite of the high percentage of B ovis excretors, few clinical signs of epididymitis were detected in the flock during the last 3 years of the study. It was hypothesized that vaccination protected rams against the clinical disease but not the carrier state. The importance of culturing semen for assessment of a control program was emphasized.
Bulgin
M S
MS
University of Idaho, Department of Veterinary Science, Caldwell 83605.
D000818:Animals; D002002:Brucella / Q000302:isolation & purification*; D002006:Brucellosis / Q000382:microbiology / Q000517:prevention & control / Q000662:veterinary*; D002353:Carrier State / Q000382:microbiology / Q000662:veterinary; D004823:Epididymitis / Q000382:microbiology / Q000517:prevention & control / Q000662:veterinary*; D007958:Leukocyte Count / Q000662:veterinary; D008297:Male; D012661:Semen / Q000382:microbiology*; D012756:Sheep; D012757:Sheep Diseases / Q000382:microbiology / Q000517:prevention & control*; D013737:Testis / Q000473:pathology; D014611:Vaccination / Q000662:veterinary